1. Technical Field
The present invention relates to collaborative information collection and recording, and more particularly to efficiently recording collaborative audio-visual documents.
2. Description of the Related Art
Collaboration systems typically combine audio/video conferencing with one or more objects that conference participants collaborate on. One type of collaboration is, for example, screen-sharing, but the system may also be a mash-up of many objects including video windows. The collaboration screen thus consists of several components, and is typically very large or even full screen, with a possibility of expanding to multiple screens.
Recording these collaboration screens in high quality is difficult and requires a large amount of memory and consumes a significant amount of computing resources. To be able to play back on existing audio/video players the recording is typically made as a single audio/video, where the audio and video are data compressed using standard encoding techniques, such as H.264 for video. The real-time encoding of a large video at a reasonable frame rate requires a large amount of CPU resources. For example, encoding a single 1280×960 frame with H.264 on a better-than-average computer with no special hardware may take up to 0.5 seconds. This means that a frame rate of only 2 frames can be achieved, while typically 15 or even up to 30 frames per second is required.